Abstract High temperature is one of the most basic challenges faced by copper-based brake pads in emergency braking of high-speed railway train. Here, a novel copper-based brake pad was prepared and its tribological properties in the temperature ranging of 400–800 °C were studied by pin-on-disc tribometer equipped with heating chamber. The results show that compared with commercial copper-based brake pad, self-designed copper-based brake pad exhibits higher mean friction coefficient and smaller fluctuation of friction coefficient under all test conditions. The friction coefficient of self-designed copper-based brake pad is in the range of 0.35–0.45 at the temperatures up to 600 °C. At 800 °C, the failure mechanism of copper-based brake pad is related to the properties of graphite and copper. Graphite on the friction surface disappears after severe oxidation, resulting in the loss of lubrication of friction interface. Copper undergoes oxidation and softening. Oxidation makes copper unable to promote the formation of stable tribo-film, and the low-strength copper matrix after softening cannot effectively support the friction surface. Therefore, one of the key principles to design high-performance copper-based brake pad is to increase the oxidation resistance of graphite and the high temperature strength of copper matrix.

中文翻译：

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高速铁路列车用高性能铜基刹车片及其高温表面物质演化与磨损机制

摘要 高温是高铁列车紧急制动中铜基刹车片面临的最基本挑战之一。在这里，制备了一种新型铜基刹车片，并通过配备加热室的销盘式摩擦计研究了其在 400-800°C 温度范围内的摩擦学特性。结果表明，与商用铜基刹车片相比，自主设计的铜基刹车片在所有测试条件下均表现出更高的平均摩擦系数和更小的摩擦系数波动。自行设计的铜基刹车片在高达 600°C 的温度下的摩擦系数在 0.35-0.45 的范围内。在 800°C 时，铜基刹车片的失效机制与石墨和铜的特性有关。摩擦表面的石墨经过剧烈氧化后消失，导致摩擦界面失去润滑。铜会发生氧化和软化。氧化使铜无法促进稳定摩擦膜的形成，软化后的低强度铜基体无法有效支撑摩擦面。因此，设计高性能铜基刹车片的关键原则之一是增加石墨的抗氧化性和铜基的高温强度。